In recent years, various kinds of piezoelectric sensors including piezoelectric films have been devised. For example, International Publication No. 2010/143528 (Patent Document 1) discloses a piezoelectric sensor including a piezoelectric film made of polylactic acid. The piezoelectric film includes a first surface and a second surface. The piezoelectric sensor further includes four divided electrodes formed on the first surface, four wiring lines connected to the four divided electrodes, and a flat electrode formed on the second surface.
When pressed, the piezoelectric sensor of Patent Document 1 having the above configuration detects voltage generated at each divided electrode from each wiring line. The piezoelectric sensor of Patent Document 1 can output pressing information based on the detected voltage.
However, in the piezoelectric sensor of Patent Document 1, the four wiring lines overlap both the piezoelectric film and the flat electrode. For this reason, in the four wiring lines, voltage is generated from the piezoelectric film in a predetermined region overlapping both the piezoelectric film and the flat electrode. That is, the piezoelectric sensor of Patent Document 1 detects the voltage generated by the four divided electrodes and the predetermined regions of the four wiring lines.
As a result, the conventional piezoelectric sensor and the conventional touch type input device have room for improvement in that the generated voltage is correctly detected by the plurality of divided electrodes.